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Precise orbit determination for a large LEO constellation with inter-satellite links and the measurements from different ground networks:a simulation study

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Satellite Navigation 2022年第3期3卷 38-50,I0002页

作者： Xingchi He Urs Hugentobler Anja Schlicht Yufeng Nie bingbing duan Institute for Astronomical and Physical Geodesy Technical University of MunichArcisstr.2180333MunichGermany College of Surveying and Geo-Informatics Tongji UniversitySiping Road 1239Shanghai200092China

Geodetic applications of Low Earth Orbit(LEO)satellites requires accurate satellite orbits.Instead of using onboard Global Navigation Satellite System observations,this contribution treats the LEO satellite constellation independently,using Inter-Satellite Links and the measurements of different ground networks.Due to geopolitical and geographical reasons,a ground station network cannot be well distributed.We compute the impact of different ground networks(i.e.,global networks with different numbers of stations and regional networks in different areas and latitudes)on LEO satellite orbit determination with and without the inter-satellite links.The results are based on a simulated constellation of 90 LEO satellites.We find that the orbits determined using a high latitude network is worse than using a middle or low latitude network.This is because the high latitude network has a poorer geometry even if the availability of satellite measurements is higher than for the other two cases.Also,adding more stations in a regional network shows almost no improvements on the satellite orbits if the number of stations is more than 16.With the help of ISL observations,however,the satellite orbits determined with a small regional network can reach the same accuracy as that with the global network of 60 stations.Furthermore,satellite biases can be well estimated(less than 0.6 mm)and have nearly no impact on satellite orbits.It does thus not matter if they are not physically calibrated for estimating precise orbits.

关键词： LEO satellite Orbit determination Ground station distribution Inter-satellite link

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碳达峰目标如何引领城市低碳转型——来自准自然实验的证据

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数量经济技术经济研究 2024年第7期41卷 177-196页

作者：张兵兵董安然段玉婉南京农业大学经济管理学院南京农业大学资源环境与发展研究院中央财经大学国际经济与贸易学院

积极稳妥推进碳达峰碳中和不仅是破解我国资源环境约束突出难题的重要抓手,也是促进人与自然和谐共生的中国式现代化的题中之义。对此,本文构建一个委托—代理框架,揭示碳达峰目标引领低碳转型的作用机制。在此基础上,从2006~2019年低... 详细信息

积极稳妥推进碳达峰碳中和不仅是破解我国资源环境约束突出难题的重要抓手,也是促进人与自然和谐共生的中国式现代化的题中之义。对此,本文构建一个委托—代理框架,揭示碳达峰目标引领低碳转型的作用机制。在此基础上,从2006~2019年低碳试点城市的五年规划等文件,手工收集碳达峰目标设立数据,运用渐进双重差分模型识别了碳达峰目标对低碳转型的净影响。研究结果表明,碳达峰目标设立可以显著促进低碳转型。经过安慰剂、异质性处理偏误等一系列稳健性检验和内生性处理后,研究结论依然成立。碳达峰目标对低碳转型的促进效应因城市资源禀赋、市场化水平的差异以及地方政府是否面临换届而呈现显著的异质性。机制检验表明,碳达峰目标通过提高绿色技术创新水平和增加绿色环保投资进而推动城市低碳转型。进一步研究发现,相较于以强时间约束形式设定碳达峰目标,采取弱时间约束形式的碳达峰目标更有利于发挥其对城市低碳转型的引领效应。

关键词：碳达峰目标低碳转型绿色技术创新绿色环保投资双重差分模型

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越南槐叶绿体基因组序列特征与系统发育分析

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分子植物育种 2024年第11期22卷 3563-3573页

作者：段娜雷海英刘兵兵长治学院生命科学系长治046011 山西大学黄土高原研究所太原030006

越南槐(Sophora tonkinensis)是豆科苦参属的一种灌木,具有重要的药用价值和生态功能。由于其野生种群濒临灭绝,迫切需要对其进行保护。此外,对于市场需求而言,野生越南槐资源非常有限,市场上存在许多掺假产品。因此,需要建立一种在分... 详细信息

越南槐(Sophora tonkinensis)是豆科苦参属的一种灌木,具有重要的药用价值和生态功能。由于其野生种群濒临灭绝,迫切需要对其进行保护。此外,对于市场需求而言,野生越南槐资源非常有限,市场上存在许多掺假产品。因此,需要建立一种在分子水平上鉴定越南槐及其掺假品的方法。叶绿体基因组是系统发育分析、遗传多样性评价和植物分子鉴定的重要遗传标记来源。在本研究中,我们报道了越南槐的叶绿体全基因组。结果显示,越南槐叶绿体基因组全长152234 bp,共编码126个基因即8个rRNA基因,37个tRNA基因,80个CDs基因和1个假基因(rps16),GC含量为36.40%。重复序列分析共检测到68个复杂重复序列和145个简单重复序列。边界分析结果显示,在越南槐中由于IR区的微收缩,导致JLA边界的rpl2和trnH基因丢失。核苷酸多态性分析共检测出3个变异热点区(trnT-GGU-psbD,rps18-rpl20和trnA-UGG-trnI-GAU),pi(π)>0.05。基于76个蛋白质编码基因序列的系统发育分析结果显示,苦参属物种聚为一个单系支,支持率达100%。本研究对越南槐及其近缘种的比较分析将有助于制定有效的保护和管理策略,并为这一重要药用植物的分子鉴定方法提供依据。

关键词：越南槐叶绿体基因组苦参属系统发育

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成长型思维对初中生学校适应的影响:学业韧性和心理脆弱性的链式中介作用

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中国健康心理学杂志 2024年第6期32卷 950-955页

作者：段冰冰刘孟娜周琰聊城大学教育科学学院心理学系 252000 山东省滨州市无棣县第三初级中学

目的:考察学业韧性和心理脆弱性在成长型思维与初中生学校适应之间的中介作用机制。方法:采用成长型思维问卷、学校适应问卷、学业韧性问卷和心理脆弱性问卷对山东省609名初中生进行调查。结果:①相关分析结果显示,成长型思维、学业韧... 详细信息

目的:考察学业韧性和心理脆弱性在成长型思维与初中生学校适应之间的中介作用机制。方法:采用成长型思维问卷、学校适应问卷、学业韧性问卷和心理脆弱性问卷对山东省609名初中生进行调查。结果:①相关分析结果显示,成长型思维、学业韧性、心理脆弱性与学校适应之间均存在显著相关(r=-0.28~0.72,P<0.01);②中介效应检验表明,成长型思维对初中生学校适应的直接效应显著,效应值为0.21;学业韧性和心理脆弱性在成长型思维和初中生学校适应之间均起到单独中介作用,中介效应值分别为0.24、0.05,并且也起到链式中介作用,效应值为0.07。结论:成长型思维不仅能直接影响初中生的学校适应,而且还能通过学业韧性和心理脆弱性对初中生学校适应产生间接影响。

关键词：成长型思维学校适应心理脆弱性学业韧性初中生

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Fungal diversity rather than bacterial diversity drives the ecosystem multifunctionality of vineyards in a semi-arid region

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International Journal of Agricultural and Biological Engineering 2021年第6期14卷 126-136页

作者： bingbing duan Yizhao Ren Leqi Zhang Chenxing Suzhou Guoqiao Chen Ping Cui Yusong Zhangyang Wei Liu Hasmik Merkeryan Xu Liu College of Enology Northwest A&F UniversityYangling 712100ShaanxiChina Penglai Wine College Yantai Institute of Science and TechnologyYantai 265600ShandongChina Grape Industrial Park Management Committee of the Eastern Foot of Helan Mountain in Ningxia Yinchuan 750004China Horticulture Research Institute Sichuan Academy of Agricultural SciencesChengdu 610066China Ningxia Helan Mountain’s East Foothill Wine Experiment and Demonstration Station of Northwest A&F University Yongning 750104NingxiaChina

The presence of multiple ecosystem functions and services(i.e.,ecosystem multifunctionality)has been proven to be maintained by biodiversity in natural terrestrial ecosystems.However,the mechanisms by which microbial diversity drives ecosystem functions in vineyards and the effects of ecosystem functions on wine quality remain unknown.Here,fifteen vineyards from five wine sub-regions(Shizuishan,Yinchuan,Yuquanying,Qingtongxia,and Hongsipu)in Ningxia were selected to assess the microbial community structure,ecosystem multifunctionality,and wine quality.Overall,each index differed among the vineyards from these five wine sub-regions in Ningxia.High-throughput sequencing revealed that bacterial and fungal communities varied among these vineyards.Bacterial communities were dominated by Actinobacteria,Proteobacteria,Chloroflexi,and Acidobacteria.Ascomycota was the dominant fungal phylum,followed by Basidiomycota and Mortierellomycota.In addition,fungal Shannon diversity rather than bacterial Shannon diversity showed a positive relationship with ecosystem multifunctionality.Correlation analysis revealed that ecosystem multifunctionality was positively correlated with wine acidity and negatively correlated with pH value and residual sugar content of wine.Soil chemical functions exhibited relationships with wine quality being similar to those of ecosystem multifunctionality;i.e.,positively related to wine acidity but negatively related to wine pH and residual sugar content.However,soil physical functions were negatively correlated with the alcohol and anthocyanin content of wine.The research results show that the ecosystem functions maintained by fungal diversity could be attributed to wine quality of vineyards.

关键词： microbial diversity multifunctionality terroir wine quality wine sub-regions

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Application of variance component estimation（VCE） in orbit determination with low Earth orbit（LEO） satellite constellation

Application of variance component estimation（VCE） in orbit...

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第十三届中国卫星导航年会

作者： Xingchi He Urs Hugentobler Yufeng Nie bingbing duan Institute for Astronomical and Physical Geodesy Technical University of Munich College of Surveying and Geo-Informatics Tongji University

In recent years, low Earth orbit（LEO） satellite constellations have become a hot topic. Precise orbit determination of these LEO satellites is one of the fundamental requirements. In addition to traditional observations from ground stations, inter-satellite link（ISL） is often proposed as an effective way to improve constellation autonomy and orbit accuracy. However, due to the different characteristics and accuracies of two types of observations, combing these data for orbit determination requires additional attention. Variance component estimation（VCE） is one of the commonly used methods to adjust the weights of multi-source data. This simulation study investigates the application of VCE in LEO satellite orbit determination using both ground tracking and ISL data. Without VCE, by applying an equal weight to both types of observations, orbit errors are about two times larger than by applying the computed weights using VCE. We also show that for computation efficiency, a simplified VCE algorithm is more favorable. For a constellation with 120 satellites, this simplified algorithm is more than 2400 times faster without losing orbit accuracy. We also discuss the impact of modelling errors on VCE. The estimated variance components are contaminated by the modelling errors and are deviated from the true measurement accuracy.

关键词： Variance component estimation LEO satellites Inter-satellite link Orbit determination

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渭北旱塬老藤酿酒葡萄资源的品种特性研究

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核农学报 2024年第4期38卷 746-754页

作者：张佳静索雨洁段冰冰李雅善谭立杭刘旭姜建福夏永秀西北农林科技大学葡萄酒学院陕西杨陵712100 香格里拉酒业股份有限公司云南迪庆674400 中国农业科学院郑州果树研究所河南郑州450009 中国林业科学研究院华北林业实验中心北京102300

为了保护与开发我国渭北旱塬地区的老藤酿酒葡萄种质资源,本研究以白玫瑰和红玫瑰两份老藤酿酒葡萄资源为材料,对其植物学特性、生长结果习性、枝条直立性、抗寒性、果实性状以及酿酒特性等进行了系统比较。结果表明,白玫瑰和红玫瑰葡... 详细信息

为了保护与开发我国渭北旱塬地区的老藤酿酒葡萄种质资源,本研究以白玫瑰和红玫瑰两份老藤酿酒葡萄资源为材料,对其植物学特性、生长结果习性、枝条直立性、抗寒性、果实性状以及酿酒特性等进行了系统比较。结果表明,白玫瑰和红玫瑰葡萄枝条粗壮直立,与赤霞珠葡萄相比,其新梢木质部宽度明显增加,木质素分布区域更大,枝条机械性能与负荷能力更强,适合无架栽培。白玫瑰和红玫瑰葡萄萌芽率、结果枝率、结果系数、平均株产量均较高,两者丰产性均较好。白玫瑰和红玫瑰葡萄枝条均具有较强的抗低温能力,在渭北旱塬地区无需埋土防寒越冬。白玫瑰葡萄果皮淡绿色带有浅红晕,成熟果实还原糖和可滴定酸含量分别为195.17和5.97 g·L^(-1),果皮酚类物质含量较低,适合酿造清爽的干白葡萄酒;红玫瑰葡萄果皮紫红色,成熟果实还原糖和可滴定酸含量分别为208.33和3.64 g·L^(-1),果皮富含花色苷等酚类物质,可酿造清新的桃红葡萄酒。采用小容器酿造的干白葡萄酒酒度为11.12%(V/V),总酸含量为5.06 g·L^(-1),总糖含量为2.70 g·L^(-1);桃红葡萄酒酒度为12.97%(V/V),总酸含量为4.69 g·L^(-1),总糖含量为2.87 g·L^(-1)。两份老藤酿酒葡萄资源果实及其酿造的葡萄酒均具有玫瑰香味。本研究为酿酒葡萄新品种选育提供了一定的参考。

关键词：老藤酿酒葡萄品种特性直立性无架栽培

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浸渍方式对高海拔‘赤霞珠’葡萄酒挥发性风味物质的影响

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中外葡萄与葡萄酒 2024年第1期 65-73页

作者：梅源苏周晨星谭立杭郭宾索雨洁段冰冰闫银芳刘旭西北农林科技大学葡萄酒学院陕西杨凌712100 四川省农业科学院农产品加工研究所四川成都610011 香格里拉酒业股份有限公司云南迪庆674400 五粮液仙林生态酒业有限公司四川宜宾644007

以我国西南高山葡萄酒产区的‘赤霞珠’葡萄为原料,采用不同浸渍方式进行酿造,通过对葡萄酒理化指标和挥发性香气成分进行检测分析,明确浸渍方式对高海拔葡萄酒挥发性香气品质的影响。结果表明,发酵后延长浸渍处理的酒样具有更高的可滴... 详细信息

以我国西南高山葡萄酒产区的‘赤霞珠’葡萄为原料,采用不同浸渍方式进行酿造,通过对葡萄酒理化指标和挥发性香气成分进行检测分析,明确浸渍方式对高海拔葡萄酒挥发性香气品质的影响。结果表明,发酵后延长浸渍处理的酒样具有更高的可滴定酸、酒精度、残糖和总酚含量;不同浸渍处理下酒样的挥发性物质中均以醇类和酯类物质含量较高,但处理间风味物质组成差异较大;发酵前冷浸渍处理酒样的风味物质最多,达到61种,其主要差异化合物为异戊醇、正己醇和苯乙醇等具有花香和青草香的醇类化合物;发酵后延长浸渍处理酒样的差异化合物种类更加丰富,且以呈甜果香的乙酸乙酯等酯类化合物含量更高。感官评价结果表明,与常规浸渍发酵相比,发酵前冷浸渍和发酵后延长浸渍处理的酒样呈现出更强的花果香和香料味,且发酵后延长浸渍处理酿造的葡萄酒具有更浓郁的果香和更复杂的风味结构。本研究结果为优化我国高海拔地区优质葡萄酒的酿造工艺提供了一定的参考。

关键词：挥发性风味物质浸渍工艺高海拔气相色谱-质谱联用葡萄酒

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Power-law Spectrum Analysis on Uncertainties of Rate Estimated from GPS Coordinates Time Series

Power-law Spectrum Analysis on Uncertainties of Rate Estimat...

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第九届中国卫星导航学术年会

作者： Qingchen Zhang bingbing duan Urs Hugentobler Technische Universit?t München

The ground station velocity derived from GPS coordinates time series is one of the important elements for assessing the stability of the global reference frame. Precisely characterizing this parameter includes finding the reliable uncertainty of the station velocity. In the article, we present a method to monitor velocity uncertainties from GPS coordinates time series which are corrupted by temporally correlated noise. A power-law noise plus white noise model is used in the research to prevent underestimation of the uncertainties and is parameterized in terms of orthonormal wavelet bases. Then the unknown parameters of the noise model can be iteratively estimated by the expectation-maximization algorithm and can be applied in Kalman filter. Nevertheless, different from white noise and random walk noise which can be characterized by an integer-ordered transfer function, the power-law noise in the GPS coordinates time series is mathematically described by fractional-order calculus, which means that it is impossible to find a finite integer-ordered filter to fit its straight line spectrum for all frequencies. As a consequence, an Oustaloup’s filter based numerical algorithm is developed to build a feasible state-space model describing such power-law noise. By applying the proposed state-space model in the Kalman filter, it is possible to estimate the velocity uncertainties in the real-time and the viability of the algorithm is verified by the results from simulations and the data of IGS station WTZR.

关键词： Power-law noise GPS time series Wavelets Kalman filter

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Genome-wide analysis of GH3 gene family in soybean( Glycine max)

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Oil Crop Science 2016年第2期1卷 1-9页

作者： Wei ZHAO Xinjie SHEN Wei GUO Qingbo YOU Yanjie YAO Jianhua LU Juncheng ZHANG Lei HUANG bingbing duan Huarong LV Aili BAO Yongqing JIAO Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of AgricultureOil Crops Research Institute of the Chinese Academy of Agricultural Sciences

Auxin,as an important phytohormone,regulates plant growth and development by regulating the expression of diverse genes.GH3 is one of the main auxin-responsive genes,and has crucial roles in many biology processes.Studies have demonstrated GH3 gene family in various plants,but no gehome-wide analysis of the GH3 gene family has been conducted for a legume species.Here we performed a comprehensive genome mining and identified a total of 24 GH3 genes,located on 13 different chromosomes in the soybean genome (GmGH3.1 to GmGH3.24).Most of the predicted GmGH3s clustered together in pairs,reflecting the ancient genome duplication event.Analysis of gene structure revealed the presence of introns in protein-coding regions,and that their size,abundance and distribution varied within the gene family.Expression analysis of GmGH3 genes in soybean various tissues of different developmental stages displayed their temporally and spatially expression patterns.We have identified 24 GH3 genes in the soybean genome.The expansion of GmGH3 genes and their distribution pattern on the chromosomes revealed genome-wide segmental duplications of soybean.Diverse expression of GmGH3s during soybean growth and development indicated their important function roles.

关键词： GH3 IAA gene family soybean

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